Improvement in locks



. To all persons to whom these presents may come:

awo-dw Salar @anni @Wire `DANIEL B. READ AND JAMES n. cLAPP, oEPnovIDENoE, NHODEISLAND, ASSIGNoRS, BY MESNE ASSIGNMENTS, fro o. @.moKERMAN, or BOSTON, MASSACHUSETTS.

Letters Patent No. 100,556, dated Mfr/rch 8, 1870. v

`IIIMERO'VIElNIENT IN LOCKS The Schedule referred to in these Letters Patent and making part of the same.

Be it known that we, DANIEL B. READ and J AMES H. Clusif?, of Providence, of the county of Providence, aud State of Rhode Island, have invented a new and i useful Improvement in Locks for Doors; and do hercby declare the same `to be fully described inV the following specification and represented in the accompanying drawings, of which'- i Figure 1 denotes a view of' a lock-oase with its capplate removed, and with our improvement as connected with the tumblers a'pplied to the main bolt of such case. l

'Figure 2 is a horizontal section of the lock, taken just above and so as to exhibit the tumblers.

Fignre is a side view of the key.

The nature of our invention consists in so combining a. level' and a double spring or counter-springs witheach pair ot' tumhlers` that when one'of such tumblers is beingmoved upward by the key the said tumbler, through such lever, shall cause the other tumbler to be simultaneously moved in an opposite direction,

the doublespring or `counter-spring operating to re-' 'store the tumblersto their normal positions after such action of the key.

In the drawingsv i A denotes the case of thelock;

B, the main bolt; O, the latch-bolt; and D E, the pair of tumbler-S o1-slide plates applied to thecase so as to operate .with the main bolt and its stud a, in the usual manner. l

A double-armed s ring, F, or counter-springs, are soapplied to both t mblers as to press'one of them downward and the other of them npward.

Over the two 'tumblers is a lever, G, which is supported by and so as to turn freely ou a stud or fulcrum, b. f One arm Vof the said` lever rests against the top of one tumbler and the other arm rests against the top of the other tumbler. y

The key lla-sfthree bits, f y, separated by equal spaces, 7| fi. f

The middle bit is to operate one of the tnmblers,

viz: that one which is to bc elevated.

eg serveito aotuate the main bolt.

Wlien'the key is inserted in the lock from. one side of it, one of the bits eg will actuate the main bolt The other bits while the key is being turned in the right direction in the look, but when the key is introduced from the opposite4 side of vthe lock the other of the two bits e g will operate the main bolt while the key is being so revolved.

' The principle of our invention may be carried ont with a greater number of pairs of tumblers, in which case one-halt' the number of tumbler-S will be moved in one andthe other half will be moved in the oppo# V'itnesses:

R. H. PUEINTOJ, HLRAM D. CAHooN. 

